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Revision History for A280681

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Showing entries 1-10 | older changes

A280681

Numbers k such that Fibonacci(k) is a totient.
(history; published version)

#44 by Alois P. Heinz at Mon Aug 03 04:24:12 EDT 2020

STATUS

proposed

approved

#43 by Michel Marcus at Mon Aug 03 03:41:59 EDT 2020

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editing

proposed

#42 by Michel Marcus at Mon Aug 03 03:41:53 EDT 2020

COMMENTS

From _Robert Israel_, Aug 02 2020: (Start) All terms > 2 are multiples of 3, because Fibonacci(k) is odd unless k is a multiple of 3. Are all terms > 3 multiples of 6? If a term k is not a multiple of 6, then since Fibonacci(k) is not divisible by 4, Fibonacci(k)+1 must be in A114871. (End)- _Robert Israel_, Aug 02 2020

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proposed

editing

#41 by Altug Alkan at Mon Aug 03 03:38:57 EDT 2020

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editing

proposed

#40 by Altug Alkan at Mon Aug 03 03:15:48 EDT 2020

COMMENTS

The answer for above question is yes. All terms > 3 are multiples of 6. - Altug Alkan, Aug 03 2020

Discussion

Mon Aug 03

03:38

Altug Alkan: Maybe it is better if I write to Mr. Israel. Best regards.

#39 by Altug Alkan at Mon Aug 03 03:12:21 EDT 2020

COMMENTS

The answer for above question is yes. All terms > 3 are multiples of 6. - Altug Alkan, Aug 03 2020

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approved

editing

#38 by N. J. A. Sloane at Sun Aug 02 15:32:59 EDT 2020

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proposed

approved

#37 by Robert Israel at Sun Aug 02 13:36:08 EDT 2020

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editing

proposed

#36 by Robert Israel at Sun Aug 02 13:34:55 EDT 2020

MAPLE

select(k -> numtheory:-invphi(combinat:-fibonacci(k))<>[], [1, 2, seq(i, i=3..100, 3)]); # Robert Israel, Aug 02 2020

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proposed

editing

#35 by Robert Israel at Sun Aug 02 13:33:31 EDT 2020

STATUS

editing

proposed